1. Field of the Invention
The present invention relates generally to boardwalks used as pedestrian walkway, service vehicles and the like along oceans, lakes and rivers and the like, which can be readily turned into protective walls for flood control.
2. Prior Art
Boardwalks are constructed close to shore in many areas to provide pedestrians a walkway overlooking beaches. The boardwalks are also sometimes used by relatively light service vehicles, food carts, and the like.
Boardwalks are very popular with residents and visitors during good weather and particularly during summer times. Current boardwalks are constructed as a single purpose structure, namely to serve as a walkway for sightseeing, enjoying the weather, doing exercise, and the like, without having to encounter sand, dirt or mud or a rough terrain. Current boardwalks are also prone to damage from wind, hurricanes and flooding.
Boardwalks close to the shores are generally constructed by assembling planks made out of wood or synthetic materials over a constructed frame structure. In a typical plank deck assembly, decking planks are mounted to a deck frame in uniformly spaced apart relationship to allow surface water or rain to pass through the deck as well as to aid in ventilation. The spacing selected for use between the deck planks may vary depending on the type of materials used in construction as well as anticipated environmental conditions. Deck builders employ various implements to maintain uniformity in deck plank spacing, including wooden spacers, nails or specially made jigs. Some boardwalks are prevented from uplifting merely by their weight and some others are provided with certain anchoring foundation to resist wind and other natural uplifting forces.
Currently, boardwalks close to the shores are generally constructed by assembling planks made out of wood or synthetic materials over a constructed frame structure. An example of such structures of prior art is described in the U.S. Pat. No. 8,522,505 and as shown in FIG. 1. In such a boardwalk system construction, a plurality of piles or supports 12 are positioned on the ground surface over which the boardwalk to be installed. Each pile 12 is used to support one or more horizontally-extending beams 14 thereon. Each support 12 rests on the ground surface and elevate the beams 14 to the desired position above the ground. If desired, the beams 14 can be coupled to the associated support(s) 12 by any of a wide variety of coupling devices or systems. Each beam 14 supports a plurality of generally horizontally extending planks 16. This arrangement may however varied such that each plank 16 is supported by more than one beam 14, or by only a single beam 14, in which case the tread 16 may be supported at its other end by the earth or other structures. Generally, upper surface of each plank is flat and planar, and positioned relatively close to the upper surface of an associated plank 16 such that upper surfaces together define a generally smooth surface, usually with gaps between the planks 16, which can be walked upon, ridden upon by small vehicles and the like, etc. To make the boardwalk system more strong, each plank 16 may be coupled to an adjacent plank 16 by, for example, a laterally-extending tongue 15 received in an associated groove 17 in the adjacent plank 16. The supports 12, beams 14 and planks 16 can be made from any of a wide variety of materials, including, but not limited to, wood, wood composite materials or other composite materials, concrete, or materials made entirely or primarily of concrete. Modular decking systems having some features similar to that shown in FIG. 1 and described herein are disclosed in U.S. Pat. No. 5,906,084 to Millington et al. Each illustrated beam 14 may also include a plurality of pre-formed recesses 20 formed therein, formed in the outer surface thereof. Each beam 14, in the schematic of FIG. 1, includes four recesses 20 along its length. Each beam recess 20 may then be aligned with an associated plank recess 18 to together cooperate to form an opening 22 which can receive a connector 24 therein.
In almost all boardwalks, as discussed above, spacing is provided between the deck planks 16 depending on the type of materials used in construction as well as anticipated environmental conditions to allow for material expansion, to allow rain drainage as well as to provide for ventilation through the deck.
During storms and hurricanes or in the case of a Tsunami, the coastal areas require protection from flooding. Sea level rise due to global warming is increasing the frequency of coastal flooding, particularly in low lying and flat beach areas. Flooding protection is also needed on many river banks and lake shores when the water rises, for example, during long periods of heavy rains or during sudden warming of the weather after heavy snows.
Various types of barricades are used to protect coastal areas and floodplains from flooding. These are either permanent structures in the form of floodwalls, seawalls, dikes, and levees, or are temporary barricades such as sand bags or other portable barriers in various shapes, forms, and materials.
Permanent flood protection structures create a physical and visual obstruction to and from the waterfront, which makes them infeasible in populated low lying and flat beach areas where flood protection is most needed. Temporary flood protection structures have limited application, long response time, and entail significant effort and cost for deployment and later removal.
The construction of boardwalks as well as flood protection structures for coastal areas, lakeshores and riverbanks are costly. Flood protection is also usually needed only a few days in a year or even in a few years. It would therefore be highly advantageous if boardwalk structures could be designed such that they would double as flood protection structures. Such novel boardwalks must be capable of supporting the wind and wave and water loads when deployed as a flood protection structure. They should also be capable of being readily deployed and withstand the harsh and corrosive environment of seashore.
It is appreciated by those skilled in the art that events such as hurricanes produce large waves, winds as well as high speed gusts. It is therefore important for the boardwalks to be capable of not only withstanding the generated waves, raised water levels and winds, but be also capable of withstanding gusts, which are sometimes significantly higher in speed than the wind levels.